For certain applications, the transfer of fluids from one enclosure to another must be done in such a way as to prevent contamination of the fluid being transferred. For example, in the pharmaceutical, biotech, diagnostic and dairy industries, fluids (e.g., samples) are routinely transferred from a dispensing enclosure to a receiving enclosure, without introducing contaminating material into the receiving enclosure.
The word “enclosure” as used herein refers to any closed containment structure without respect to its size. Thus it includes such small enclosures as cans which may be used in shipping starter bacteria from a culture lab. On the other end of the size spectrum, it includes large tanks, which may have capacities of several thousand gallons, or more, such as are used in the dairy processing industry.
The apparatus for aseptic transfer of material between enclosures described in U.S. Pat. No. 4,941,517 (the '517 patent), which is incorporated by reference herein in its entirety, provided a helpful means for the aseptic transfer of fluids. The apparatus includes a fluid receiver assembly comprising an adapter and a fluid receiver fitting mounted therein. The fluid receiver fitting comprises a seal member, channel member and covering film. The fitting includes a plurality of needle guide channels leading from the outside of the fluid receiver assembly toward the interior of the enclosure and a seal at the ends of the channels. A pierceable self-closing seal is provided between ends of each of the channels and the interior of the enclosure.
For purposes of providing background relating to the present invention, the fluid receiver assembly of the '517 patent is now discussed with reference to drawing figures provided in that application. The drawing figures are renumbered in this specification from the drawing figure numbers provided in the '517 patent.
FIGS. 1, 2, 3 and 4 of the present specification respectively correspond to FIGS. 11, 6, 8 and 10 of the '517 patent. FIG. 1 shows a cross-section of the overall fluid receiver assembly (FRA) 12 installed on a wall 16 of an enclosure, while FIG. 2 depicts a cross-section of a seal member 26 portion of the FRA 12; FIG. 3 depicts a cross-section of a channel member 28 portion of the FRA 12 and FIG. 4 is a cross-sectional view of a fluid receiver fitting 93 portion of the FRA 12 formed by the combination of the seal member 26 and channel member 28.
In particular, as shown in FIG. 1, the fluid receiver assembly 12 includes an adapter 24, the seal member 26, the channel member 28, a retaining ring 30, and a cover film 31. The FRA 12 is incorporated into a wall of an enclosure such as wall 16 of a tank (not shown) by means of weld 34.
Seal member 26 has generally opposing first and second surfaces 58 and 60 respectively. The first surface 58 has a first generally outwardly projecting central portion 62 which is shown convex, and an upstanding outer wall portion 64 generally corresponding to an outer wall of adapter 24. Penetration zone 66 is between wall portion 64 and central portion 62. Penetration zone 66 is generally coextensive with the circumference of the first surface at its lower terminus between upstanding wall portion 64 and central portion 62.
Second surface 60 has a plurality of bottom portions 68 (also referred as seal elements), an upstanding wall portion 70, and a surface central portion 72. Each of the seal elements forms a projection extending downwardly from the seal means. The projections, in combination, define an array thereof. Interrupting surface wall portions 74 extend upwardly from, and between adjacent bottom portions 68, and interface with bridging walls 52 in adapter 24. Bottom portions 68 are aligned with penetration zone 66. Upstanding wall portions 64 and 70 together generally define a wall 71 between them.
The penetration zone 66 includes a main surface 66M comprising the majority of the surface area of the penetration zone. Recesses 67 extend from the main surface 66M toward bottom portions 68. One bottom portion 68 fits into each of the holes of adapter 24. Seal member 26 is preferably made from rubber, e.g., based on ethylene propylenediene monomer terpolymer (EPDM), or other elastomers, e.g., those derived from, or modified with, butene, isoprene, ethylene, and the like.
Channel member 28 is seen to have generally opposing first bottom and second top surfaces 76 and 78 respectively. First bottom surface 76 has a first bottom portion 80, including optional projections 81, a second upstanding wall portion 82, and a third central portion 84. A plurality of tapered needle guide channels 86 extend between the first and second surfaces and are encompassed, on their lower ends, adjacent bottom surface 76, with projections 81, which include the lower ends of channels 86. Channels 86 are preferably countersunk at their lower, narrower ends as seen at 87. The axes 88 of the channels diverge from each other, traversing from top 78 to bottom 76. The axes 88 also diverge from central axis 90 of the channel member, when traversing from the top of the channel member as at 78 toward the bottom. In each of needle channels 86, that surface 94 which most closely approaches the central axis 90 also diverges, top to bottom, from central axis 90 along the channel length. Thus is the downward divergence of the channels 86 established with respect to the central axis, with respect to each other, and with respect to the central axis as related to those surfaces 94 of the channels which most closely approach the central axis.
Channel member 28 is made of a material that is normally not penetrable by conventional hypodermic needles, e.g., one of the engineering plastics, such as nylon, polypropylene, or high density polyethylene. The penetrability of channel member 28 is thus provided by the pre-formed needle channels 86, which extend through the channel member from top 78 to bottom 76.
Fluid receiver fitting 93 is seen in FIG. 4. It comprises the seal member 26, the channel member 28, and the covering film 31, and has a first outer surface corresponding to the second surface 60 as shown in FIG. 1. The first inner surface of the receiver fitting 93 corresponds to the first surface 58 of seal member 26. The second inner surface of the fitting corresponds to surface 76 of channel member 28. The second outer surface of fitting 93 corresponds in general to surface 78 of channel member 28. In keeping with the relatively small thickness of covering film 31, the second outer surface of the fitting generally includes the entire thickness of film 31. Thus film 31 covers the ends of needle channels 86 of channel member 28. Cover film 31 which covers the outer surfaces of needle channels 86 at the points they intersect the surface 78 of channel member 28 may be made from any of a plurality of readily pierceable film materials.
The second inner surface of fitting 93 includes a first surface portion corresponding to the bottom portion 80, including projections 81, which is in contact with penetration zone 66 of seal member 26, preferably over all of the contiguous surfaces of bottom portion 80 and penetration zone 66. Projections 81, which comprise extensions of needle channels 86, are aligned with, and fit into, recesses 67 in seal member 26.
The central surface portion 84 of the second inner surface is optionally concave, whereby it cooperatively receives the central portion 62 of the first inner surface of seal member 26, which is optionally convex. Thus, central surface portion 84 cooperates in receiving the strengthening and stabilizing central core member 38 of adapter 24. As seen in FIG. 4, surfaces 62 and 84 preferably share a common interface about their contiguous surfaces.
The apparatus is useful for aseptically transferring material into an enclosure such as a tank. The adapter 24 is preferably permanently installed in a wall or other outer member of an enclosure such as a tank, e.g., as shown in FIG. 1. After the adapter 24 has been installed, a receiver fitting 93 is installed in adapter 24.
Fitting 93 is installed in adapter 24, to make fluid receiver assembly 12, by bringing surface 60 of seal member 26 into surface contact with the surfaces about channel 46, namely, inserting fitting 93 into adapter 24, with seal member 26 facing the adapter. The adapter, the seal member, and the channel member are jointly configured and adapted to assure the alignment of channels 86 with holes in adapter, with an intervening pierceable, self-closing portion of the seal member corresponding to penetration zone 66. This alignment assures an unimpeded passage of needles through the fitting 93 along paths prescribed for the needles. With the fitting thus aligned in the adapter, retaining ring 30 is emplaced and secured, whereby the installation of fitting 93 into tank (not shown) is completed. As retaining ring 30 is tightened, it seats against flange 92 of channel member 28, whereby seal member 26 is compressed between adapter 24 and channel member 28. As seal member 26 is compressed, bottom portions 68 are urged into holes of adapter. As the compression progresses, additional rubber flows through the holes of adapter and extends the original contours of bottom portions 68 further beyond the interior surface 44 of the adapter, such that the combinations of the original bottom portions 68 plus the additional material appear as nipples 154 comprising a greater amount of the rubber material than only the bottom portions 68, on the inside surface of the tank, as seen in, for example, FIG. 1.
The fluid receiver assembly 12 is configured to receive one or a plurality of needles, wherein each needle connects in fluid communication with a delivering enclosure to provide the aseptic transfer of fluid from the dispensing enclosure to the receiving enclosure. To provide aseptic fluid communication between the two enclosures, each needle punctures the film 31, enters a respective channel 86, and penetrates the penetration zone 66 until emerging through the bottom portions 68 to the interior of the receiving disclosure.
Up until now, commercial manufacture of the fluid receiver fitting 93 described in the '517 patent and above has involved assembly of its separately manufactured components, namely the seal member 26, the channel member 28 and the covering film 31. As described in the '517 patent, the mating surfaces of the fluid receiver fitting's components are adhesively bonded to one another. See '517 patent at col. 15, line 53 to col. 16, line 2. This method of manufacturing the fluid receiver fitting is suboptimal. One problem is that manufacture of separate components for assembly requires tight tolerances that complicate the manufacturing process. The need to maintain tight tolerances is particularly important for the fluid receiver fitting, which is to be used for aseptic fluid transfer. In that application, improperly or even loosely assembled parts presents an unacceptable risk of contamination. Further, the adhesives that are used to bond the components carry residual solvents which themselves can be a source of contamination. This risk is unacceptable given the intended use of the fluid receiver fitting.
There is thus a need for a fluid receiver fitting and a process for making the same, which does not require assembly of separate components, does not employ the use of bonding adhesives or fasteners to complete the assembly, and provides for closing off a core or hole formed in a needle penetration zone of the seal member where the sampled fluid is a liquid stream.